Apparatus for removing deposits from stills.



N. W. THOMPSON. APPARATUS FOR REMOVING DEPOSITS FROM STILLS.

APPLICATION FILED AUGJZ. I91].

UNITED STATES PATENT OFFICE.

NELSON W. THOMPSON, OF OAKLAND, CALIFORNIA, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO SHELL COMPANY OF CALIFORNIA, OF SAN FRANCISCO, CALIFORNIA, A

CORPORATION OF CALIFORNIA.

Specification of Letters Patent.

Patented Mar. 25, 1919.

Application filed August 27, 1917. Serial No. 188,521.

To all whom it may concern:

Be it known that I, NELSON W. THOMP- SON, a citizen of the United States, residing at Oakland, in the county of Alameda and State of California, have invented a new and useful Apparatus for Removing Deposits from Stills, of which the following is a specification. Myl invention relates to an apparatus used for t e purpose of removing deposits such as carbon from the walls of a still. In the treatment of petroleum oils, for the purpose .of lowerin the boiling point and increasing their v0 atility, and particularly in such stills used in the cracking process, the oil is subjected to considerable temperature and pres- I sure, and durin such treatment considerable carbon is free from the oil. Thls carbon has a-great ailinity for metal and deposlts and accumulates on the metal surfaces of the apparatus in which the operation is being performed, and it is the principal object of my invention to produce a device of simple form and construction by means of which the carbon is prevented from accumulating on such metal surfaces during the distilling operation.

It is a further object of my invention to facilitate the removal of the carbon so re- 80 moved and also the heavy residuum from the bottom of the vessel in which the operation is being carried on.

Further objects and advantages will appear hereinafter in the following description.

85 Referring to the drawings, which are for illustrative purposes only:

' Figure 1 1s a vertical sectional view of a still having a deposit removing device therein embodying a form of my invention.

Fig. 2 is an enlarged sectional inverted plan view on line 2-2 of Fig. 1.

Fig. 3 is an enlarged sectional plan view on line 3.-3 of Fig. 1, and

Fig.- 4 is an enlarged sectional plan view 45 on line 4-4 of Fig. 1.

11 designates a cylindrical shell forming a vertical still having secured thereto at its upper end a circular-flange 12 to which is secured by means of bolts 13 a head 14, the

60 head having oil inlet connection 15 and a vapor outlet connection 16. 18 designates a circular flange secured to the lower end of the still 11fto which is secured-by means of suitable bolts 19 a cylindrical connection 20,

the flange 22 by means of suitable rivets, such member 24 bein in alinement with and forming a continuation of the still 11. Secured to the lower end of the member 24 is a circular flange 25 to which is secured by means of suitable bolts 26 a reducer connection 27, this reducer connection being adapted to be connected to a suitable pump for removing the heavy material from the member 24.

30 designates a spider formed on the inside of the flange 18, and 31 designates a spider formed on the inside of the connection 20 at the lower end thereof. The spider 30 is provided with a flanged bushing 32 and the spider 31 is provided with a similar bushin 33. 35 designates a vertical shaft mount in the bushings 32 and-33, the shaft 35 being provided with a collar 36 adapted to engage the upper face of the bushing 32 and support the shaft in a vertical position therein.

38 designates a'Worm wheel secured to the shaft 35 in any suitable manner, this worm wheel bein in mesh with a worm 39 mounted on a driving shaft 40, the driving shaft 40 being properly mounted in the walls of the connection 20 as clearly shown in Fig. 3, and the shaft 40 being driven from any suitable outer source not shown.

41 designates a man hole formed inside of the connection 20 and 42 designates a suitable cover secured to the man hole by means of bolts 43. 44 designates a flanged outlet on the side of the connection 20 adapted to be connected to a suitable pipe, the flange 44 forming an outlet for the lighter products from the still.

45 designates a vertical pipe secured by means of a bolt 46 to the upper end of the shaft 35, the upper end of the pipe 45 bein rotatably mounted in a circular flange 4% formed on the inside of the head 14, such flange extending upwardly and forming an extension on the connection 16 which is adapted to be connected to suitable piping for the purpose of carrying off the vapors from the still as hereinafter described.

Secured to the pipe 45 in any suitable manner and directly under the head 14 is a 'upwardly and into the vapor column 45 through openings 54 to the vapor outlet 16. Secured to the pipe 45 between the cones 51 and 52 is a cone 56 of smaller diameter than the cones heretofore referred to, similar cones 57 and 58 being secured to the pipe under the "cone 52. Under each of the smaller cones 56, 57 and 58 are openlngs 54 in the pipe 45 so that any vapors collecting under such small cones pass into the pipe or vapor column 45.

60 designates arms secured at intervals to the pipe 45 by means of suitable rivets'61, the outer ends of the arms 60 engaging therebetween vertically arranged scraping members consisting of" vertically extending blades 62, the outer edges of which are arranged to freely rotate within the walls of the still, the blades 62 being secured to the arms 60 by means of suitable rivets 63. The cones 51 and 52 are slotted as indicated at 65 to receive the blades 62.

Formed as a part of and extending downwardly from the inner side of the head 14 are'four scrapers 66, the lower edge of which are adapted to remove any accumulation from the upper cone 50. Secured to the lower end of the shaft 35 by means of a suitable bolt 68 is a pipe 69, the lower end of the pipe extending into the reducer 27.

designates a spiral scraper or conveyer secured to the pipe 69 by suitable arms 71. The lower end of the spiral 70 is formed to fit within the tapered wallsof the conveyer and remove any deposits therefrom as hereinafter referred to.

The device operates in the following manner:

Heated oil is introduced to the still through the inlet connection 15 and falls upon the cone 50. This cone 50 spreads the oil against the inner Wall of the still whereon the oil runs downwardly giving off its va- .pors which pass into the vapor column 45 through the openings therein under the small'cones, eventually passing out of the still through the outlet connection 16. The unvaporized oil asses downwardly over the wall of the still the cone 52 assisting in spreading the oil against the Wall of the still. The heavy oil or residuum collects in the reducer 27 and in the member 24, the lighter oil bein drawn off from the still through theout et connection 44. The oil in the still deposits carbon upon the sides of the still and upon the sides of the member 24, building up thereon unless the same is removed.

During the distillingoperation the shaft 40 is driven as hereinbefore referred to, the worm thereondriving the Worm wheel 38.

v the Worm wheel 38 drives the shaft 35, im

parts a rotarv movement to the vapor column 45 and the pipe 69. This rotary movement of the vapor column rotates the blades 62 within the still and continuously removes from the inner walls thereof any deposits upon the same thereby preventing a deposit of carbon forming on the inner walls of the still. The deposit so removed from the walls of the still moves'downwardly with the oil and passes into the tubular member or collection chamber 24 where it mixes with'the residuum therein. The residuum is drawn from the reducer 27 by a pumpas heretofore referred to and the carbon deposits'removed therewith, the carbon being prevented from forming upon the inner walls of the member 24 by the scraper 70.

A still constructed as above described, in

which the carbon is continuously removed during the distilling operation, is capable of running without the interruptions in the operation which are usually necessary for the purpose of removing the deposits from the still, and thereby greatly increases the efiiciency of the plant.

What I claim is 1. In combination, a vertically arranged still, oil inlet means at the top of the still, oil outlet means at the bottom of the still, a hollow column rotatably mounted in the still having openings to permit the outflow of' vapors therethrough, spreader devices in-- the still to cause the oil to flow downwardly over the inner walls of the still, scraping devices mounted on said column arranged to remove deposits from the inner walls of the still, and means for rotating said column during the distilling operation.

2. In combination, a vertically arranged still, a collection chamber at the bottom of the still, oil inlet means at the top of the still, oil outlet means at the bottom of the still, residuum outlet means at the bottom of the collection chamber, a vapor column rotatably mounted in the still having openings therein to permit the flow of vapors from the still into the column, vapor outlet means for said column in the top of the still, spreader means on said column for causing the oil to flow over the inner wall of the still, scrapers mounted on said vapor column arranged to remove deposits from the inner walls of the still, a spiral scraper in said collection chamber arranged to remove deposits from the inner walls of the collection chamber, and means for rotating the scrapers in the still and collection chamber during the operation of the still.

3. In combination, a vertically arranged still, a collection chamber at the bottom of the still, oil inlet means at the top of the still, oil outlet means at the bottom of the still, residuum outlet means at the bottom of the collection chamber, a vapor column rotatably mounted in the still having openings therein to permit the flow of vapors from the still into the column, vapor outlet means for said column in the top of the still spreader means on said column for causing the oil to flow over the inner wall of the still, scrapers mounted on said vapor column arranged to remove deposits from the inner Walls of the still, a shaft secured to the lower end of the vapor column, an extension on said shaft extending downwardly into the collection chamber, a spiral scraper mounted on said extension arranged to remove deposits from the inner walls of the collection chamber and cause the residuum to move downwardly therein, and means for driving said shaft.

In testimony whereof I have hereunto set my hand at San Francisco, California, this 20th day of August, 1917.

NELSON W. THOMPSON. 

